[DETAIL] The bio balls is suitable for fresh water and sea water tank. Great help to restore the natural water quality, and provide the most suitable living environment for your fishes. This product can be used in a variety of filters, pls place in the appropriate position of the filter. Features: The bio balls are fired by high temperature. Full of rich variety of natural elements and essential minerals and trace elements. Encourages growth of biological colonies and holds large amounts of good bacteria. Great help to restore the natural water quality, and provide the most suitable living environment for your fishes. Suitable for fresh water and sea water tank. Reduces ammonia and nitrate levels. Any problem, please contact our store without hesitation. Honor to serve you! Specification: Name: Aquarium filter media ball Color: Yellow Material: Quartz Diameter of ball: 21mm Package Information: Package size: 14 * 10 * 3cm / 5.51 * 3.94 * 1.18in Package weight: 85g Plastic Packaging Package List: 20* Aquarium filter media ball Shipping: 1.We guarantee to ship goods out within 24-72 hour after payment confirmation except holiday. 2.We ship by China post,HKpost EMS,DHL,Fedex,according to your choice when placing orders . 3.If you didn't receive the item after 45 days,please feel free to contact us.We will make all our effort to resolve the problem. 4.We are not responsible for delays causedby the customs,Import duties,taxes or other customscharges. Warranty: 1.All items have 1 year guarantee.IF your purchase do not meet merchantable quality, fitness for purpose or match the description, We can make sure your issues are resolved . 2.For wrongly-shipped items, Please contact us in 48 hours after delivery.We will arrange to deliver the correct items or return all your payment. 3.For defective or faulty products,please take photos or videos,we would resend or refund after confirmation. [ATTRIBUTES] - Hign-concerned Chemical: None - Voltage: Other - Origin: Mainland China - Hign-concerned Chemical: None - Voltage: Other - Origin: Mainland China - Power (W): None - Type: fish